The once formidable Myanmar military is cracking from within – riddled with spies secretly working for the pro-democracy rebels, the BBC has found.

The military only has full control of less than a quarter of Myanmar’s territory, a BBC World Service investigation reveals.

The junta still controls the major cities and remains “extremely dangerous” according to the UN special rapporteur on Myanmar. But it has lost significant territory over the past 12 months.

The soldier spies are known as “Watermelons” – green on the outside, rebel red within. Outwardly loyal to the military but secretly working for the pro-democracy rebels whose symbolic colour is red.

A major based in central Myanmar says it was the military’s brutality that prompted him to switch sides.

“I saw the bodies of tortured civilians. I shed tears,” says Kyaw [not his real name]. “How can they be so cruel against our own people? We are meant to protect civilians, but now we’re killing people. It’s no longer an army, it’s a force that terrorises.”

More than 20,000 people have been detained and thousands killed, the UN says, since the military seized power in a coup in February 2021 – triggering an uprising.

Kyaw initially thought about defecting from the army, but decided with his wife that becoming a spy was “the best way to serve the revolution”.

When he judges it safe to do so, he leaks internal military information to the People’s Defense Forces [PDF] – a network of civilian militia groups. The rebels use the intelligence to mount ambushes on the military or to avoid attacks. Kyaw also sends them some of his wage, so they can buy weapons.

Spies like him are helping the resistance achieve what was once unthinkable.

The BBC assessed the power balance in more than 14,000 village groups as of mid-November this year, and found the military only has full control of 21% of Myanmar’s territory, nearly four years on from the start of the conflict.

The investigation reveals that ethnic armies and a patchwork of resistance groups now control 42% of the country’s land mass. Much of the remaining area is contested.

The military now controls less than at any time since they first took control of the country in 1962, according to the US-based Armed Conflict Location and Event Data Project (Acled).

Co-ordinated operations between ethnic armies and civilian militia groups have put the military on the back foot.

After heavy territorial losses earlier this year Commander-in-Chief Min Aung Hlaing made a rare admission that his forces were under pressure.

The leaked Watermelon intelligence from within the military is helping to tip the balance. Two years ago, the resistance set up a specialised unit to manage the growing network of spies and to recruit more.

Agents like Win Aung [not his real name] collect the Watermelon leaks, verify them where possible, and then pass them on to the rebel leaders in the relevant area.

He is a former intelligence officer who defected to the resistance after the coup. He says they are now getting new Watermelons every week and social media is a key recruitment tool.

Their spies, he says, range from low-ranking soldiers to high-ranking officers. They also claim to have Watermelons in the military government – “from the ministries down to village heads”.

They are put through a strict verification process to ensure they are not double agents.

Motivations for becoming a spy vary. While in Kyaw’s case it was anger, for a man we are calling “Moe” – a corporal in the navy – it was simply a desire to survive for his young family.

His wife, pregnant at the time, pushed him to do so, convinced the military was losing and he would die in battle.

He began leaking information to the Watermelon unit about weapons and troop movements.

This kind of intelligence is crucial, says pro-democracy rebel leader Daeva.

The ultimate goal of his resistance unit is to take control of Yangon, Myanmar’s biggest city and his former home. But they are a long way off.

The military retains the majority of major urban areas – home to crucial infrastructure and revenue.

“It’s easier said than done to attack and occupy [Yangon], Daeva says. “The enemy will not give up on [it] easily.”

Unable to physically penetrate the city, Daeva from his jungle base directs targeted attacks by underground cells in Yangon using Watermelon intelligence.

In August, we witnessed him making one such call. We were not given the details but were told it was to direct an assassination attempt on a colonel.

“We will do it inside the enemy’s security parameters,” he told them. “Be careful, the enemy is losing in every direction,” he added, telling them that this meant they were more likely to be on alert for infiltrators and spies.

Daeva says several major attacks by his unit have been the result of tip-offs.

“We started with nothing and now look at our success,” says Daeva.

But it comes at a cost. Watermelons have to live in fear of both sides, as navy corporal-turned spy Moe discovered.

Deployed from Yangon to Rakhine – a border region where the military is fighting an ethnic group siding with the resistance – he had to live with the terror that his intelligence could mean he himself was attacked.

In March this year, his anchored ship was hit with a projectile missile, followed by open fire. “There was no place to run. We were like rats in a cage.” Seven of his fellow soldiers were killed in the rebel attack.

“Our ability to protect [the moles] is very limited,” admits Win Aung. “We can’t publicly announce that they are Watermelons. And we can’t stop our forces from attacking any particular military convoy.”

He says that when this is explained to the Watermelons, however, they do not falter. Some have even responded: “When it comes to that moment, don’t hesitate, shoot.”

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But there are times when the spies can no longer bear the danger.

When Moe was set to be sent to another dangerous front line, he asked the Watermelon unit to smuggle him out into a resistance-controlled area. They do this using an underground network of monasteries and safe houses.

He left in the dead of night. The next morning, when he did not show up for duty, soldiers came round to the house. They interrogated his wife Cho, but she remained tight-lipped.

After days on the run Moe arrived at one of Daeva’s bases. Daeva thanked him over video call, before asking him what role he wanted to play now. Moe replied that, given his young family, he would like a non-combat role and would instead share his knowledge of military training.

A few weeks later he crossed into Thailand. Cho and the children fled their home too and hope to eventually join him and build a new life there.

The military is aggressively trying to reclaim lost territory, carrying out a wave of deadly bombings. With Chinese- and Russian-made fighter jets, it is in the air that it has the upper hand. It knows that the resistance is far from being one homogenous group and is seeking to exploit divisions between them.

“As the junta loses control, their brutality increases. It’s getting worse. The loss of life… the brutality, the torture as they lose ground, literally and figuratively,” says UN special rapporteur Tom Andrews.

The military is also conducting sweeps for Watermelons.

“When I heard about the sweeps, I stopped for a while,” says Kyaw. He says he always acts like a staunch supporter of the military to avoid unwanted attention.

But he is scared and doesn’t know how long he can stay hidden. Defecting is not an option, as he worries about abandoning his ageing parents, so for now, he will keep acting as a military spy, hoping to see a day when the revolution is over.

If and when that day comes, Watermelons like Kyaw and Moe will not be forgotten, Win Aung vows.

“We will treat them with honor, and allow them to choose what they want to do next in their lives.”

The military did not respond to the BBC’s request for an interview.

About the data:

Researchers commissioned by the BBC questioned multiple sources from 12 February to 13 November 2024 for each of more than 14,000 village groups to assess the level of military control in their area.

The names and boundaries of village groups were sourced from the Myanmar Information Management Unit, or MIMU, which is hosted by the UN Development Programme (UNDP).

In every case, the research team spoke to at least one source with no official affiliation to the military or the opposition – such as academics, charity workers, journalists and local residents.

When sources provided conflicting information for a village group, unaffiliated sources were prioritised and further cross-referenced with media reporting.

Responses were divided into three possible categories of control:

• Military: The military is present and active in the region. It operates a local administration or provides certain public services, which are all functioning normally.
• Contested: The military is present in the region, but there are limits to its effective control. This could include areas where general administration and public services are not fully operational, or where the military divides administration with regional ethnic armed forces. It also covers areas where opposition forces can enter and exit, and where skirmishes between opposing forces occur.
• Resistance groups and ethnic armies: The military is largely absent and has not performed on-the-ground operations for more than three months. Civil services may be provided by resistance forces, ethnic armies or a civilian government, likely supported by a rebel armed militia.

Some parts of the country are designated as forest and are not mapped onto village groups. They have different administration structures, mainly dealing with resource extraction and conservation. The BBC has opted to focus on the areas of Myanmar which have a clearly defined system of governance.

Additional reporting by Becky Dale, Muskeen Liddar, Phil Leake, Callum Thomson, Pilar Tomas, Charlotte Attwood and Kelvin Brown. Methodology support by Prof Lee Jones, Queen Mary University of London.